# Difference between revisions of "Topics:PCG Portfolio"

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;Crystal structures and their transformations | ;Crystal structures and their transformations | ||

− | + | * Space Group Symmetry | |

− | + | * Symmetry lowering | |

− | + | * Structural phase transitions – Landau theory | |

− | + | * Representation analysis | |

− | + | * Tensors in crystallography | |

− | + | * Charge density | |

− | + | * Modulated crystal structures – Superspace group approach | |

− | Elastic properties | + | ;Elastic properties |

• Strain-stress relations | • Strain-stress relations |

## Revision as of 09:51, 2 March 2007

## PCG – Educational portfolio

- Crystal structures and their transformations

- Space Group Symmetry
- Symmetry lowering
- Structural phase transitions – Landau theory
- Representation analysis
- Tensors in crystallography
- Charge density
- Modulated crystal structures – Superspace group approach

- Elastic properties

• Strain-stress relations • Pressure effects

Bulk properties

• Thermal expansion in crystals • Atomic displacement parameters: relationship with phonons and specific heat.

Magnetic structures

• Description of magnetic structures – propagation vectors • Magnetic symmetry analysis – irreps and coreps • Spin density determination with polarised neutrons. • XYZ and spherical polarimetry applied to crystalline materials

Microstructure analysis

• Strain effects • Particle size and distribution • Stacking faults • Texture

Diffraction methods

• CW neutron and x-rays • TOF neutrons • Energy dispersive x-rays • Diffraction imaging – TEDDI etc. • Time-resolved crystallography • Crystallography under high pressure • High-magnetic-field crystallography • SX techniques: Laue, time-sorted Laue…

Data analysis

• Refinement of structural parameters –least square – Rietveld • Direct-space methods – simulated annealing • Single-crystal techniques – twinning

Instrumentation

• Diffraction geometries • Principles of TOF/CW instrument design • Detector technologies of X-rays and neutrons